1. Field of the Invention
The present invention relates to a battery charge control device which charges a battery of a marine vessel by a power generator attached to an engine of a propulsion device. More specifically, the present invention relates to a battery charger which charges a main battery to be used for operations of the engine of the propulsion device and an accessory battery to be used for power supply to devices other than the engine. Further, the present invention relates to a marine vessel including such a battery charger.
2. Description of Related Art
An example of a propulsion device included in a marine vessel is an outboard motor. The outboard motor includes an engine, a propeller to which a driving force is transmitted from the engine, and a power generator attached to the engine. Power necessary for operating the engine is supplied to the outboard motor from a main battery installed in a hull. This main battery is connected to the power generator. During operation of the engine, the main battery is charged by power generated by the power generator.
On the other hand, in a marine vessel, various meters and gauges, a fish finder, a GPS receiver, and other electric components may be provided. Further, in a comparatively large-scaled vessel, an electric range, a microwave, an electric refrigerator, an electric freezer, and other electric devices may be provided in the cabin. To supply power to these devices, an accessory battery may be installed in the hull separately from the main battery. Power of the main battery is used for operating the engine, and power of the accessory battery is supplied to other devices.
U.S. Pat. No. 5,111,132 discloses a charger which commonly charges the main battery and the accessory battery by a power generator provided in the engine of an outboard motor. In this charger, the main battery and the accessory battery are connected in parallel to the power generator. To prevent a current flow between the batteries, a battery isolator using a rectifier circuit is provided. This charger includes a control circuit which stops or regulates charging of the main battery and the accessory battery when a voltage of the main battery or a voltage of the accessory battery reaches a regulation voltage determined in advance.